Sosuke Aizen

That's right. Captain Aizen isn't scary because he uses Kyōka Suigetsu. Kyōka Suigetsu is a terrifying power but there are lots of guys who'd rather die than obey him if that was all he had. Those crazy Espadas all had their individual motives but were brought together by one thing. His strength. Captain Aizen's powers are without equal. Beware of Kyōka Suigetsu? No. That's reckless. Beware of everything else? No. That's reckless too. The sky falling, the Earth cracking open... you can all put your wits together to prepare for all kinds of calamities, but Captain Aizen's powers are far beyond any precautions.

„

~ Gin describing Aizen's powers

“

No one stands on the top of the world. Not you, not me, not even gods. But the unbearable vacancy of the throne in the sky is over. From now on...I will be sitting on it.

Yes. It seems the Chrysalis stage is over. What a relief. Now I can witness the end of the Soul Society with my own eyes.

„

~ Aizen

“

Fear is necessary to achieve evolution. The fear that, in one's current state, one could quite possibly be destroyed at any time. I thank you, Gin. It is thanks to your presence that I have finally succeeded in surpassing both Shinigami and Hollows.

Summary

Sōsuke Aizen (藍染 惣右介, Aizen Sōsuke) is the former captain of the 5th Division in the Gotei 13. He later leaves Soul Society with his followers, Gin Ichimaru and Kaname Tōsen. His lieutenant was Momo Hinamori. He formerly served as the lieutenant of the 5th Division under Shinji Hirako. After waging war against Soul Society with an army of Arrancar, Aizen was defeated by Ichigo Kurosaki and sealed away by Kisuke Urahara, and then imprisoned for his crimes.

Resistance to Soul Manipulation, Paralysis Inducement (NaNaNa's The Underbelly is somewhat ineffective on him as it can only immobilize him for short amount periods of times, even with most of his spiritual power is restricted and his black coat making it easier for NaNaNa's abilities to work) and Space-Time Manipulation (Was able to destroy Kōtotsu and only strayed from his course slightly. Being chased by Kōtotsu can throw someone to a different time period)

Attack Potency:Country level (Far superior to all of the Espada) | At least Country level (Stronger than before as he fused with the Hōgyoku which grants him more power) | At least Country level (Gained reiryoku and reiatsu far superior to standard spiritual beings) | At least Country level (Far stronger than before) | Multi-Continent level (Far stronger than before, Able to hurt Post-Dangai Ichigo | Large Planet level (Comparable to Ichigo, was also stated by Urahara to have turned stronger)

Speed:Relativistic (Far superior to the Espada) | Relativistic (Faster than before) | At least Relativistic (Even faster than before) | At least Relativistic, likely higher (Could cut down Gin before he could react) | Massively FTL (Faster than before; could hit Post-Dangai Ichigo and grab him | Massively FTL (Kept up with Yhwach in their fight)

Durability:Country level | At least Country level (Survived a forbidden Kidō from Yamamoto, took a Getsuga Tenshō from Post-Resurrection Bankai Hollow Mask Ichigo) | At least Country level (Tanked multiple attacks from Isshin, Yoruichi and Urahara) | Multi-Continent level (Was able to survive a slash from Dangai Ichigo who was able to destroy a small mountain by the pressure of the slash alone), immortality and regeneration also make him hard to kill | Multi-Continent level (More durable than before. Survived Ichigo's Mugetsu due to the Hogyoku) | Large Planet level (Took attacks from Post-Power Absorption Yhwach)

Range: Extended melee range with physical strikes, tens to hundreds of meters with various Kidō spells (some of his Kidō blasts have been shown as dwarfing entire city blocks), hundreds of kilometers with Fragor and Ultra Fragor, thousands of kilometers with Hadō #90: Kurohitsugi during the Thousand Year Blood War Arc.

Hogyoku: A powerful object originally created by Kisuke Urahara. Once equipped, Aizen is granted the ability of high-speed regeneration, and constant evolution in the form of more powerful transformations. However, should he be pushed beyond his limits, the Hogyoku would backfire on him and no longer consider him to be the true wielder of the Hogyoku.

Caja Negacion: These cubes are capable of sealing away an enemy from the battlefield for a very long time, even foes that are far stronger, however the time limit for the stronger foes is much shorter than those on the same level as him.

Reiatsu Concealing Cloak: A cloak created by Urahara which hides the wearer's Reiatsu. Aizen used this cloak to sneak up and attack Isshin Shiba. Aizen states it allows the wearer to blend in with the air around them by incorporating Kidō into the cloak, almost completely concealing them from sight.

Intelligence: Extraordinary Genius. Arguably, the most fearsome trait of Aizen is his tremendous intellect. He is well-versed in the history, strategy, and tactics of Soul Society, and is privy to knowledge unknown to many, such as the existence of the Ōken, as well as the obscure method in which to create one. He has created several Hollows and Arrancar while avoiding arousing any suspicion from the majority of his fellow Shinigami. For over 110 years, he had been engaging in experiments which involved unique and highly dangerous manipulations of Reiryoku and Reishi, including experiments involving the Hollowfication of Shinigami, something which had never been done before. He has an innate knowledge of the Hōgyoku, rivaling that of its creator, Kisuke Urahara; he even knows how to destroy it. He figured out the true nature of Shinji Hirako's Shikai and deduced it produces an optical illusion, allowing him to counter its effect. He effectively deduces the true nature of the Hōgyoku via trial and error of the situations which revolve around it. He was also aware of several events, which happened in separate dimensions, as he knew about Ichigo fighting and winning against Grimmjow and Ulquiorra, while simultaneously awakening a "new power", despite being in the Real World with the Espada at that time.

Weaknesses: His Zanpakutō's special ability can be overcome by touching its blade before it is released, and he is somewhat overconfident. He can only use his Reality Warping when possessing the Hogyoku.

Notable Attacks/Techniques:

Shunpo: A Shinigami movement technique which allows the user to move faster than the eye can follow. As speed is the main factor of the technique, the method is best characterized by how fast one can get from point A to point B in the least amount of steps.

Shikai: The initial release to a Shinigami's Zanpakutō. It is activated by a command while declaring the name of the Zanpakutō Spirit. It changes the shape of the Zanpakutō and/or granting special abilities. Aizen's Shikai is Kyouka Suigetsu, released on the command "Shatter".

Perfect Hypnosis: Aizen can control the 5 senses of his opponents with the Shikai of his Zanpakutō, who'll be completely succumbed to the Hypnosis once activated.

El Escudo: A light green Reiatsu barrier that Aizen can summon around his person to block an incoming attack.

Millón Escudo: An advanced form of El Escudo, Millón Escudo is simply a million El Escudo that Aizen can form around any part of his body for even greater protection.

Bakudō #26: Kyokkō:A spell that bends light in order to hide the caster, their Reiryoku, Reiatsu or their Kidō.

Hadō #63: Raikōhō: Lightning Reiryoku is gathered into the caster's arm and released towards the target like a shock-wave.

Bakudō #81: Dankū: Upon activation, the caster generates a barrier that is capable of the complete nullification of any Hadō of the level 89 or lower. However, this barrier is not solely limited to Hadō as it can nullify the effects of abilities that are similar to Hadō.

Hadō #90: Kurohitsugi: The target is sealed inside a large black coffin and are seemingly cut while inside. A large torrent of gravity is located inside that distorts space and time while restricting any chance for escape.

Hadō #99: Goryūtenmetsu: Five large pillars of light are generated around the caster composed of Reiatsu that resemble large dragons. A forbidden Kidō as it not only destroys the surroundings, it absorbs nearby Reiatsu to enhance itself.